The Research Center in Oral Biology will function to expand dental research at the State University of New York at Buffalo into three integrated projects: (I) Salivary Defense Factors; (II) Bacterial Virulence Factors; and (III) Host Response Systems. The scientific theme of this RCOB is the Modulation of Natural Defense in Oral Disease. It is our expectation that the RCOB will provide a mechanism whereby dental researchers at SUNY/Buffalo can combine their areas of scientific expertise with modern technology to begin our next generation of studies. The foundation for this RCOB is in place and is enhanced by: 1) a group of dedicated scientists with an established productive record in dental research; and 2) a commitment of support from the University and the School of Dental Medicine; and 3) the existence of a Periodontal Disease Clinical Research Center and Salivary Dysfunction Center which would utilize basic information gained from an RCOB to develop new treatment modalities for plaque mediated diseases and salivary dysfunctions. Project I (Salivary Defense Factors) represents a new generation of research aimed at enhancing the protective functions of saliva. This project utilizes modern technologies in protein and carbohydrate chemistry, biophysics, and computer modeling to design and synthesize salivary substances with enhanced functions relating to bacterial clearance/adherence mechanisms and lubrication. Information obtained could lead to the design of more effective artificial salivas which are custom-designed for a patient's individual needs. Project II (Bacterial Virulence Factors) is designed to identify characteristics of black-pigmenting Bacteroides which are determinants of virulence and to study the immunochemical, biochemical, and molecular biological mechanisms by which virulence is expressed. This group of organisms has been chosen for study since they are proposed to play a predominant role in odontogenic infections. Information obtained could provide a rationale for improving host defenses during the susceptible stages of Bacteroides infection. Project III (Host Response Systems) provides new initiatives to further our understanding of host response to oral bacterial infections. Host responses to be studied include the role of the neutrophil in host defense, cellular mechanism involved in the activation of bone resorption, mechanisms of bacterial mediated connective tissue invasion, and factors involved in the regeneration of the periodontal attachment apparatus. Information obtained should lead to innovative approaches to enhance host resistance to tissue destruction and regeneration of new tissues.